阅读说明：本技术 果蔬冷藏包装用环保瓦楞原纸的制备方法 (Preparation method of environment-friendly corrugated base paper for fruit and vegetable cold storage packaging ) 是由 宋佃凤 刘金山 马昌华 李波 牛克磊 李维刚 于 2021-03-12 设计创作，主要内容包括：本发明涉及瓦楞原纸的制备技术领域,具体涉及一种果蔬冷藏包装用环保瓦楞原纸的制备方法。所述的果蔬冷藏包装用环保瓦楞原纸的制备方法,包括以下制备步骤：(1)原料选用；(2)碎解；(3)筛选净化；(4)洗涤浓缩成浆；(5)流送系统；(6)浆料上网成型；(7)压榨、预烘干；(8)施胶；(9)烘干、卷取。本发明提供一种果蔬冷藏包装用环保瓦楞原纸的制备方法,得到在高湿度环境中可以长期保持高抗压强度的瓦楞原纸,可以不受包装堆叠层数的限制,冷藏空间能得到很好的利用,减少存储的成本。(The invention relates to the technical field of corrugated medium preparation, in particular to a preparation method of environment-friendly corrugated medium for fruit and vegetable cold storage packaging. The preparation method of the environment-friendly corrugated base paper for refrigerating and packaging fruits and vegetables comprises the following preparation steps: (1) selecting raw materials; (2) crushing; (3) screening and purifying; (4) washing and concentrating into pulp; (5) a streaming system; (6) forming the slurry on a net; (7) squeezing and pre-drying; (8) sizing; (9) and (5) drying and coiling. The invention provides a preparation method of environment-friendly corrugated base paper for fruit and vegetable cold storage packaging, which can obtain the corrugated base paper capable of keeping high compressive strength for a long time in a high-humidity environment, is not limited by the number of packaging stacked layers, can well utilize cold storage space, and reduces storage cost.)

1. A preparation method of environment-friendly corrugated base paper for fruit and vegetable cold storage packaging is characterized by comprising the following steps: the preparation method comprises the following preparation steps:

(1) raw materials are selected: the waste paper raw material is 100% of A-grade national waste boxboard;

(2) crushing: white water is added into the pulp crusher, the waste paper is conveyed into the pulp crusher by a chain plate machine to be mixed and beaten into paper pulp, and impurities with larger volume are separated by a sediment well, an impurity separator and a cylindrical screen;

(3) screening and purifying: screening and purifying the waste paper after being crushed by adopting a first-section medium-concentration slag remover and a fourth-section low-concentration slag remover; screening by adopting a four-section coarse screen and a three-section fine screen;

(4) washing and concentrating into slurry: the low-concentration washing liquid enters a multi-disc concentrator for washing and concentrating, and the concentration of the slurry is concentrated to 5-10%; returning the separated turbid white water and clear white water to the front section for crushing, diluting and spraying;

(5) a streaming system: the slurry firstly passes through a three-section low-concentration slag remover, then passes through a two-section screen, and finally is diluted through a section of dilution water screen;

(6) surfing the Internet: forming the slurry on a net;

(7) squeezing and pre-drying: pressing and pre-drying the formed paper;

(8) sizing: the sizing agent prepared according to the formula is used for sizing the front side and the back side of the paper after being pre-dried;

(9) and (5) drying and coiling.

2. The preparation method of the environment-friendly corrugated base paper for the refrigerated packaging of fruits and vegetables according to claim 1, which is characterized by comprising the following steps: the impurity content of the domestic waste box plate is less than 1 percent.

3. The preparation method of the environment-friendly corrugated base paper for the refrigerated packaging of fruits and vegetables according to claim 1, which is characterized by comprising the following steps: in the step (3), the concentration of the low-concentration slag separator is controlled to be 1-2%, and the ash content of the slurry is controlled to be 9-12%; the width of the screen gap of the fine screen is 0.15-0.18mm, and the concentration is controlled at 0.8-1.2%.

4. The preparation method of the environment-friendly corrugated base paper for the refrigerated packaging of fruits and vegetables according to claim 1, which is characterized by comprising the following steps: the low-concentration washing liquid enters a multi-disc concentrator for washing and concentrating, and the concentration of the slurry is concentrated to 5-10%; the separated turbid white water and clear white water are returned to the front section for crushing, diluting and spraying.

5. The preparation method of the environment-friendly corrugated base paper for the refrigerated packaging of fruits and vegetables according to claim 1, which is characterized by comprising the following steps: in the step (5), the concentration of the screen in front of the screen of the slurry is controlled to be 0.8-1.2%; the concentration of the dilution water sieve is controlled to be 0.25-0.35%.

6. The preparation method of the environment-friendly corrugated base paper for the refrigerated packaging of fruits and vegetables according to claim 1, which is characterized by comprising the following steps: when the pulp is formed on the net, the pulp concentration is controlled to be 0.8-1.2%, the paper web dryness of the out-of-net part is controlled to be 18-22%, and the filtrate concentration is controlled to be 0.25-0.35%.

7. The preparation method of the environment-friendly corrugated base paper for the refrigerated packaging of fruits and vegetables according to claim 1, which is characterized by comprising the following steps: the press line pressure is controlled at 250-300KN/m, the dryness of the pressed paper web is controlled at 45-50%, and the dryness of the pre-dried paper web is controlled at 92-95%.

8. The preparation method of the environment-friendly corrugated base paper for the refrigerated packaging of fruits and vegetables according to claim 1, which is characterized by comprising the following steps: the sizing agent comprises the following components in parts by weight:

9. the preparation method of the environment-friendly corrugated base paper for the refrigerated packaging of fruits and vegetables according to claim 1, which is characterized by comprising the following steps: and (8) in the sizing process, firstly adding starch and clear water into a sizing tank, introducing steam, heating to 70-80 ℃, preserving heat for 15min, introducing steam again, heating to 90-95 ℃, preserving heat for 20-50min at 90-95 ℃, adding aluminum sulfate, alkyl ketene dimer emulsion and styrene-acrylate emulsion, stirring to make the viscosity 20-100mPa.s and the temperature 60-75 ℃, and sizing the front side and the back side of the pre-dried paper.

10. The preparation method of the environment-friendly corrugated base paper for the refrigerated packaging of fruits and vegetables according to claim 1, which is characterized by comprising the following steps: in the step (9), the moisture content of the dried paper leaves is 5-8%, and the quantitative content is 160-²The 90s water absorption degree is 20-30g/m²。

Technical Field

The invention relates to the technical field of corrugated medium preparation, in particular to a preparation method of environment-friendly corrugated medium for fruit and vegetable cold storage packaging.

Background

With the continuous improvement of the living standard of people at present, people can eat fruits and vegetables in all seasons at any time, the continuous improvement of the fruit and vegetable refrigeration and preservation technology is benefited, the most common constant-temperature refrigeration house is adopted, in the environment with high humidity and low temperature, the quality of a packaging material is directly related to the storage effect of the fruits and vegetables, and the corrugated case is used as an environment-friendly and renewable packaging material, has the advantages of light weight, good buffering performance, certain water absorption, condensation prevention and the like, and is widely used.

However, in the environment with high humidity, such as 80-90% of relative humidity, the traditional corrugated case has serious attenuation of compression resistance and the attenuation of ring crush strength of more than 40%, so the number of packaging and stacking layers is limited, the refrigerating space cannot be well utilized, and the storage cost is increased.

The CN110714349A patent discloses a production process of high-strength corrugated base paper, which selects waste paper with more and longer wood fibers as raw materials, and carries out screening pulping, wherein a sizing agent is prepared by using starch, clear water and a glue boiling master batch and then carries out a sizing procedure, and a drying treatment step is carried out to obtain the high-strength corrugated base paper; however, the raw materials have been restricted in import of solid wastes in the beginning countries in recent years, and foreign waste paper materials (waste paper with more wood fibers and longer fibers, such as American waste OCC) are included therein.

The CN103321088B patent discloses a regenerated high-strength corrugated base paper and a production method thereof, wherein the regenerated high-strength corrugated base paper is prepared from 40-90% of domestic waste paper pulp and 10-60% of pulp residue, the pulp residue is subjected to pulping treatment by waste paper, pulp is prepared by pulp residue, pulp mixing and paper making are carried out, glue is applied to the front surface and the back surface of the corrugated base paper, drying and reeling are carried out to prepare the regenerated high-strength corrugated base paper, and the used sizing agents are modified starch, surface sizing agent styrene acrylic acid surface sizing agent or AKD surface sizing agent, surface sizing aluminum sulfate and defoaming agent polymerization concentrated grease defoaming agent; the raw materials are mixed domestic wastes and slag pulp, the pulping process is complex, grading and pulping are needed, the energy consumption is high, and the quality of the obtained product is unstable.

Disclosure of Invention

The technical problem to be solved by the invention is to provide a preparation method of environment-friendly corrugated base paper for fruit and vegetable cold storage packaging, the obtained corrugated base paper can keep high compressive strength for a long time in a high-humidity environment, the limitation of the number of packaging stacking layers is avoided, the cold storage space can be well utilized, and the storage cost is reduced.

The preparation method of the environment-friendly corrugated base paper for refrigerating and packaging fruits and vegetables comprises the following preparation steps:

(1) raw materials are selected: the waste paper raw material is 100% of A-grade national waste boxboard;

(2) crushing: white water is added into the pulp crusher, the waste paper is conveyed into the pulp crusher by a chain plate machine to be mixed and beaten into paper pulp, and impurities with larger volume are separated by a sediment well, an impurity separator and a cylindrical screen;

(3) screening and purifying: screening and purifying the waste paper after being crushed by adopting a first-section medium-concentration slag remover and a fourth-section low-concentration slag remover; screening by adopting a four-section coarse screen and a three-section fine screen;

(4) washing and concentrating into slurry: the low-concentration washing liquid enters a multi-disc concentrator for washing and concentrating, and the concentration of the slurry is concentrated to 5-10%; returning the separated turbid white water and clear white water to the front section for crushing, diluting and spraying;

(5) a streaming system: the slurry firstly passes through a three-section low-concentration slag remover, then passes through a two-section screen, and finally is diluted through a section of dilution water screen;

(6) surfing the Internet: forming the slurry on a net;

(7) squeezing and pre-drying: pressing and pre-drying the formed paper;

(8) sizing: the sizing agent prepared according to the formula is used for sizing the front side and the back side of the paper after being pre-dried;

(9) and (5) drying and coiling.

The impurity content of the domestic waste box plate is less than 1 percent.

In the step (3), the concentration of the low-concentration slag separator is controlled to be 1-2%, and the ash content of the slurry is controlled to be 9-12%; the width of the screen gap of the fine screen is 0.15-0.18mm, and the concentration is controlled at 0.8-1.2%.

The low-concentration washing liquid enters a multi-disc concentrator for washing and concentrating, and the concentration of the slurry is concentrated to 5-10%; the separated turbid white water and clear white water are returned to the front section for crushing, diluting and spraying.

In the step (5), the concentration of the screen in front of the screen of the slurry is controlled to be 0.8-1.2%; the concentration of the dilution water sieve is controlled to be 0.25-0.35%.

When the pulp is formed on the net, the pulp concentration is controlled to be 0.8-1.2%, the paper web dryness of the out-of-net part is controlled to be 18-22%, and the filtrate concentration is controlled to be 0.25-0.35%.

The press line pressure is controlled at 250-300KN/m, the dryness of the pressed paper web is controlled at 45-50%, and the dryness of the pre-dried paper web is controlled at 92-95%.

The sizing agent comprises the following components in parts by weight:

and (8) in the sizing process, firstly adding starch and clear water into a sizing tank, introducing steam, heating to 70-80 ℃, preserving heat for 15min, introducing steam again, heating to 90-95 ℃, preserving heat for 20-50min at 90-95 ℃, adding aluminum sulfate, alkyl ketene dimer emulsion and styrene-acrylate emulsion, stirring to make the viscosity 20-100mPa.s and the temperature 60-75 ℃, and sizing the front side and the back side of the pre-dried paper.

In the step (9), the moisture content of the dried paper leaves is 5-8%, and the quantitative content is 160-²The 90s water absorption degree is 20-30g/m²。

Specifically, the preparation method of the environment-friendly corrugated base paper for refrigerating and packaging fruits and vegetables comprises the following preparation steps:

(1) raw materials are selected: in order to ensure the performance of the final product, 100 percent of A-grade domestic waste box boards are used as waste paper raw materials, and the impurity content is less than 1 percent so as to ensure the uniformity of fiber raw materials;

(2) crushing: white water is added into the pulp crusher, the waste paper is conveyed into the pulp crusher by a chain plate machine to be mixed and beaten into paper pulp, and impurities with larger volume are separated by a sediment well, an impurity separator and a cylindrical screen;

(3) screening and purifying: the purification adopts a first-section medium-concentration slag remover and a fourth-section low-concentration slag remover, the concentration is controlled to be 1-2%, the ash content of the slurry is controlled to be 9-12%, the screening adopts a four-section coarse screen and a three-section fine screen, the width of a screen gap of the fine screen is 0.15-0.18mm, the concentration is controlled to be 0.8-1.2%, and the cleanliness of the slurry is ensured;

(4) washing and concentrating into slurry: the working procedure uses a multi-disc thickener, low-concentration washing liquid enters the multi-disc thickener for washing and concentration, the concentration of slurry is concentrated to 5-10%, and turbid white water and clear white water which are separated by washing are returned to the front section for disintegration, dilution and spraying;

(5) a streaming system:

the slurry firstly passes through a three-section low-concentration slag remover and then passes through a two-section screen, the concentration is controlled to be 0.8-1.2%, and finally the slurry is diluted through a one-section dilution water screen, the concentration is controlled to be 0.25-0.35%, the dosage of the system bactericide is 50-150ppm, the dosage of the retention aid is 200-400ppm, so that the good operability of the system is ensured;

(6) surfing the Internet: the pulp is molded by netting, the concentration of the pulp on the netting is controlled to be 0.8-1.2%, the dryness of paper web at the wire outlet part is controlled to be 18-22%, the concentration of filtrate is controlled to be 0.25-0.35%, and the paper web is ensured to have good evenness;

(7) squeezing and pre-drying: pressing and pre-drying the formed paper, wherein the pressure of a pressing line is controlled at 250-300KN/m, the dryness of the pressed paper is controlled at 45-50%, and the dryness of the pre-dried paper is controlled at 92-95%;

(8) sizing:

the sizing agent prepared according to the formula is used for sizing the front side and the back side of the paper after being pre-dried; firstly, 40-60 parts of starch, 550 parts of clear water and 550 parts of clear water are heated to 70-80 ℃ by introducing steam, the temperature is kept for 15min, the temperature is heated to 90-95 ℃ by introducing steam again, the temperature keeping time is 20-50min, 2-3 parts of aluminum sulfate, 4-8 parts of alkyl ketene dimer emulsion (AKD), 2-5 parts of styrene-acrylate emulsion (SAE), the viscosity is 20-100mPa.s, and the use temperature is 60-75 ℃;

(9) drying and coiling: the drying moisture of the paper sheet is 5-8%, and the quantitative ratio is 160-²The 90s water absorption degree is 20-30g/m²。

The horizontal ring crush index of the environment-friendly corrugated base paper for fruit and vegetable cold storage packaging is more than 11 N.m/g on average, and the ring crush index attenuation in a 90% humidity environment is within 20%.

The preparation method of the environment-friendly corrugated base paper for the refrigerated packaging of fruits and vegetables utilizes A-grade national wastes as raw materials, ensures the uniformity of fiber raw materials, is beneficial to environmental protection, and is characterized in that the preparation steps of raw material selection, crushing, screening and purifying, washing and concentrating into pulp, approach to a system, surfing on the net, squeezing, pre-drying, sizing, drying and coiling are combined with the formula of a sizing agent, so that the prepared corrugated base paper with reduced annular pressure attenuation is prepared, and the corrugated base paper is suitable for maintaining high compressive strength in a high-humidity environment for a long time.

Compared with the prior art, the invention has the following beneficial effects:

(1) by adopting the preparation method of the environment-friendly corrugated base paper for refrigerating and packaging fruits and vegetables, the prepared corrugated case has weak attenuation of compression resistance within 20% in an environment with relative high humidity of 80-90%, and meets the long-time storage requirement of fruits and vegetables in a refrigerator;

(2) by adopting the preparation method of the environment-friendly corrugated medium for refrigerating and packaging fruits and vegetables, the prepared corrugated paper box can be stacked in multiple layers, the space utilization rate of storage is increased, and the cost is reduced;

(3) the preparation method of the environment-friendly corrugated base paper for fruit and vegetable cold storage packaging is simple and convenient, easy to operate, and high in environment-friendly utilization rate of the adopted waste paper.

Drawings

Fig. 1 is a schematic view of a production process flow of an environment-friendly corrugated base paper for cold storage and packaging of fruits and vegetables.

Detailed Description

The present invention will be described with reference to examples, but the present invention is not limited thereto.

Example 1

The preparation method of the environment-friendly corrugated base paper for refrigerating and packaging fruits and vegetables comprises the following steps:

(1) raw materials are selected: selecting 100% of waste paper raw materials of a national waste boxboard A;

(2) crushing: white water is added into the pulp crusher, the waste paper is conveyed into the pulp crusher by a chain plate machine to be mixed and beaten into paper pulp, and impurities with larger volume are separated by a sediment well, an impurity separator and a cylindrical screen;

(3) screening and purifying: the purification adopts a first-section medium-concentration slag remover and a fourth-section low-concentration slag remover, the concentration is controlled at 2 percent, the ash content of the slurry is controlled at 12 percent, the screening adopts a four-section coarse screen and a three-section fine screen, the width of a screen seam of the fine screen is 0.18mm, the concentration is controlled at 1.2 percent, and the cleanliness of the slurry is ensured;

(4) washing and concentrating into slurry: the working procedure uses a multi-disc thickener, low-concentration washing liquid enters the multi-disc thickener for washing and concentration, the concentration of slurry is concentrated to 10%, and separated turbid white water and clear white water return to the front section for disintegration, dilution and spraying;

(5) a streaming system:

the slurry firstly passes through a three-section low-concentration slag remover and then passes through a two-section screen, the concentration is controlled to be 1.2 percent, and finally the slurry passes through a section of dilution water screen, the concentration is controlled to be 0.35 percent, the using amount of a system bactericide is 150ppm, and the using amount of a retention aid is 400ppm, so that the good operability of the system is ensured;

(6) surfing the Internet: the pulp is molded by netting, the concentration of the pulp on the netting is controlled to be 1.2 percent, the dryness of the paper web at the out-of-net part is controlled to be 22 percent, the concentration of the filtrate is controlled to be 0.35 percent, and the paper web is ensured to have good evenness;

(7) squeezing and pre-drying: pressing and pre-drying the formed paper, wherein the pressure of a pressing line is controlled at 300KN/m, the dryness of the pressed paper is controlled at 50%, and the dryness of the pre-dried paper is controlled at 95%;

(8) sizing:

sizing the paper after pre-drying by using the sizing agent prepared according to the formula; firstly, 60 parts of starch and 550 parts of clear water are heated to 70-80 ℃ by introducing steam, the temperature is kept for 15min, the boiling temperature is 95 ℃ by introducing steam again, the temperature keeping time is 50min, 3 parts of aluminum sulfate, 8 parts of alkyl ketene dimer emulsion (AKD), 5 parts of styrene-acrylate emulsion (SAE), the viscosity is 90mPa.s, and the use temperature is 75 ℃;

(9) drying and coiling: the dried moisture content of the paper sheet is 8 percent, and the fixed quantity is 180g/m²The 90s water absorption degree is 30g/m²。

The ring crush index detection standard of the environment-friendly corrugated base paper for the vegetable refrigeration packaging prepared by the steps is GB/T2679.8-1995, the water absorption detection standard is GB/T1540, and the viscosity detection standard is GB/T1548-200.

The detection result is as follows: the transverse ring pressure index is 12.8 N.m/g, and the ring pressure index decays to 16.3 percent after the ring pressure filter is placed in an environment with 90 percent of humidity for 8 hours.

Example 2

The preparation method of the environment-friendly corrugated base paper for refrigerating and packaging fruits and vegetables comprises the following steps:

(1) raw materials are selected: selecting 100% of waste paper raw materials of a national waste boxboard A;

(2) crushing: white water is added into the pulp crusher, the waste paper is conveyed into the pulp crusher by a chain plate machine to be mixed and beaten into paper pulp, and impurities with larger volume are separated by a sediment well, an impurity separator and a cylindrical screen;

(3) screening and purifying: the purification adopts a first-section medium-concentration slag remover and a fourth-section low-concentration slag remover, the concentration is controlled to be 1 percent, the ash content of the slurry is controlled to be 9 percent, the screening adopts a four-section coarse screen and a three-section fine screen, the width of a screen slot of the fine screen is 0.15mm, the concentration is controlled to be 0.8 percent, and the cleanliness of the slurry is ensured;

(4) washing and concentrating into slurry: the working procedure uses a multi-disc thickener, low-concentration washing liquid enters the multi-disc thickener for washing and concentration, the concentration of slurry is concentrated to 5%, and separated turbid white water and clear white water return to the front section for disintegration, dilution and spraying;

(5) a streaming system:

the slurry firstly passes through a three-section low-concentration slag remover and then passes through a two-section screen, the concentration is controlled to be 0.8 percent, and finally the slurry passes through a section of dilution water screen, the concentration is controlled to be 0.25 percent, the using amount of a system bactericide is 50ppm, and the using amount of a retention aid is 200ppm, so that the good operability of the system is ensured;

(6) surfing the Internet: the pulp is molded by netting, the concentration of the pulp on the netting is 0.8%, the dryness of paper web at the out-of-net part is 18%, the concentration of filtrate is 0.25%, and the paper web is ensured to have good evenness;

(7) squeezing and pre-drying: pressing and pre-drying the formed paper, wherein the pressure of a pressing line is controlled to be 250KN/m, the dryness of the pressed paper is controlled to be 45%, and the dryness of the pre-dried paper is controlled to be 92%;

(8) sizing:

sizing the paper after pre-drying by using the sizing agent prepared according to the formula; firstly, introducing steam into 40 parts of starch and 450 parts of clear water, heating to 70-80 ℃, preserving heat for 15min, introducing steam again, decocting at 90 ℃, preserving heat for 20min, introducing 2 parts of aluminum sulfate, 4 parts of alkyl ketene dimer emulsion (AKD), 2 parts of styrene-acrylate emulsion (SAE), wherein the viscosity is 30mPa.s, and the use temperature is 60 ℃;

(9) drying and coiling: the dried moisture content of the paper sheet is 5 percent and the fixed quantity is 160g/m²The 90s water absorption degree is 20g/m²。

The ring crush index detection standard of the environment-friendly corrugated base paper for the vegetable refrigeration packaging prepared by the steps is GB/T2679.8-1995, the water absorption detection standard is GB/T1540, and the viscosity detection standard is GB/T1548-200.

The detection result is as follows: the transverse ring pressure index is 11.5 N.m/g, and the ring pressure index decays to 17.2% after the ring pressure filter is placed in an environment with 90% humidity for 8 hours.

Example 3

The preparation method of the environment-friendly corrugated base paper for refrigerating and packaging fruits and vegetables comprises the following steps:

(1) raw materials are selected: selecting 100% of waste paper raw materials of a national waste boxboard A;

(2) crushing: white water is added into the pulp crusher, the waste paper is conveyed into the pulp crusher by a chain plate machine to be mixed and beaten into paper pulp, and impurities with larger volume are separated by a sediment well, an impurity separator and a cylindrical screen;

(3) screening and purifying: the purification adopts a first-section medium-concentration slag remover and a fourth-section low-concentration slag remover, the concentration is controlled to be 1.5 percent, the ash content of the slurry is controlled to be 10 percent, the screening adopts a four-section coarse screen and a three-section fine screen, the width of a screen gap of the fine screen is 0.17mm, the concentration is controlled to be 0.9 percent, and the cleanliness of the slurry is ensured;

(4) washing and concentrating into slurry: the working procedure adopts a multi-disc thickener, low-concentration washing liquid is added into the multi-disc thickener for washing and concentration, the concentration of slurry is concentrated to 8%, and separated turbid white water and clear white water return to the front section for disintegration, dilution and spraying;

(5) a streaming system:

the slurry firstly passes through a three-section low-concentration slag remover and then passes through a two-section screen, the concentration is controlled to be 1.0 percent, and finally the slurry passes through a section of dilution water screen, the concentration is controlled to be 0.3 percent, the using amount of the bactericide in the system is 100ppm, and the using amount of the retention aid is 300ppm, so that the good operability of the system is ensured; (6) surfing the Internet: the pulp is molded by netting, the concentration of the pulp on the netting is controlled to be 1.0 percent, the dryness of the paper web at the out-of-net part is controlled to be 20 percent, the concentration of the filtrate is controlled to be 0.3 percent, and the paper web is ensured to have good evenness;

(7) squeezing and pre-drying: pressing and pre-drying the formed paper, wherein the pressure of a pressing line is controlled at 280KN/m, the dryness of the pressed paper is controlled at 48%, and the dryness of the pre-dried paper is controlled at 94%;

(8) sizing:

sizing the paper after pre-drying by using the sizing agent prepared according to the formula; firstly, 50 parts of starch and 500 parts of clear water are heated to 70-80 ℃ by introducing steam, the temperature is kept for 15min, the boiling temperature is 92 ℃ by introducing steam again, the temperature keeping time is 40min, 2.5 parts of aluminum sulfate, 6 parts of alkyl ketene dimer emulsion (AKD), 3 parts of styrene-acrylate emulsion (SAE), the viscosity is 50mPa.s, and the use temperature is 70 ℃;

(9) drying and coiling: the dried moisture content of the paper sheet is 6 percent, and the fixed quantity is 170g/m²The 90s water absorption degree is 25g/m²。

The ring crush index detection standard of the environment-friendly corrugated base paper for the vegetable refrigeration packaging prepared by the steps is GB/T2679.8-1995, the water absorption detection standard is GB/T1540, and the viscosity detection standard is GB/T1548-200.

The detection result is as follows: the transverse ring pressure index is 11.9 N.m/g, and the ring pressure index decays to 14.3 percent after the ring pressure filter is placed in an environment with 90 percent of humidity for 8 hours.

Comparative example 1

The preparation method of the environment-friendly corrugated base paper for packaging comprises the following steps:

(1) raw materials are selected: 90% of domestic waste and 10% of slurry;

(2) crushing: putting the waste paper into a hydrapulper for pulping;

(3) screening and purifying: after being crushed, the pulp enters a grading sieve after passing through a high-concentration slag remover and is divided into two fibers, namely long fibers and short fibers, the grading ratio of the long fibers to the short fibers is 5:5, 10% of slag slurry is mixed into the long fibers, the slag slurry is treated by a four-section heavy slag remover and a three-section fine sieve, the long fibers are sent to a disc mill for pulping after being concentrated by a plurality of discs to prepare long fiber pulp, and the short fibers are treated by a three-section heavy slag remover and a light slag remover and then are concentrated by a plurality of discs to prepare short fiber pulp;

(4) slurry preparation: feeding the prepared long fiber and short fiber pulp into a mixed pulp blending pool to blend pulp according to the proportion of 1:1, and feeding the pulp into a paper machine pulp pool;

(5) flow conveying: the pulp enters a pulp flow box through a slag separator of a flow system and a screen in front of a net;

(6) dewatering the screen pressing part: the slurry is dehydrated through a slurry flowing box and a long net, and is squeezed through two large rolls after being discharged from a net part;

(7) drying: the paper web is dried in a drying part after leaving the pressing part, so that the dryness of the paper web reaches 93 percent;

(8) sizing: the paper web enters a sizing machine, sizing is carried out on the front side and the back side, the sizing agent is starch, water is added for stirring, amylase is added, steam is introduced for heating and pasting to obtain a starch solution with the concentration of 20% and the viscosity of 150mPa.S, the starch solution is sent to a storage tank, 2kg of aluminum sulfate per ton of paper, 2kg of surface sizing agent per ton of paper and 0.02kg of defoaming agent per ton of paper are added, and the paper web is pumped to the sizing machine for sizing after being uniformly stirred;

(9) drying and coiling: drying and coiling the sized paper web to obtain high-strength corrugated base paper, wherein the paper web contains 7% of water and has a basis weight of 170g/m²The 90s water absorption degree is 28g/m²。

The ring crush index detection standard of the corrugated base paper prepared by the steps is GB/T2679.8-1995, the water absorption detection standard is GB/T1540, and the viscosity detection standard is GB/T1548-200.

The detection result is as follows: the transverse ring pressure index is 11.5 N.m/g, and the ring pressure index decays to 43.2% after the ring pressure filter is placed in an environment with 90% humidity for 8 hours.